Chapter 3: Perception Flashcards
What are 4 characteristics of perception?
- perception can change based on added information
- perception can involve a process similar to reasoning or problem solving
- arriving at perception can involve a process
- perception occurs in conjunction with action
What is the inverse projection problem?
the task of determining the object responsible for a particular image on the retina (you’re inversing the projection on ur retina)
What is bottom up processing?
evaluating information based on how it gets from the outside world to our eyes/retina and then to our brains for higher order processing
- focuses on how without sensory information from lower funcitoning areas, we will not be able to make perceptions because objects wont be presented in our brain
What is top-down processing?
evalutating information based on how it is put together in the brain
i.e. perception involves factors such as a person’s knowledge of the environment, the expectations people bring to the perceptual situation and their attention to specific stimuli
What is recognition by components theory?
- recognition is based on basic shapes called geons and objects are defined by the series of interconnected geons
- recognition of components predicts that recognition is independent of angle view
what was the test done to show the viewing styles of individuals towards objects?
they would train people to look at an object by one particular view and then show them different/rotated view of the object…
the results showed that theres strong evidence for viewer-centered representations
what is viewer-centered representations?
representations of the object changing with position of the viewer
What is the direct pathway model of experiencing pain?
according to this model, pain occurs when receptors in the skin called nociceptors are stimulated and send their signals in a direct pathway from the skin to the brain
what has modern research shown about pain perception?
that pain can be influenced by what a person expects, how the person directs his or her attention, and the type of distracting stimuli that are present
what are four approaches to object perception?
- Helmholtz’s Theory of Unconscious Inference
- Gestalt Principle of organization
- Regularities of the Environment
- Bayesian Inference
What was helmholtz’s idea on perception in his theory of unconscious inference?
proposed that the image on the retina is ambiguous
what is the likelihood principle (helmholtz)
we perceive the object that is most likely to have caused the pattern of stimuli we have received
What is unconscious inference (helmholtz):?
our perceptions are the result of unconscious assumptions or inferences that we make about the environment
What was the Gestalt principle of organization idea on perception?
the gestalt psychologisits rejected the idea that perceptions were formed by “adding up” sensations. Instead they said elements are grouped together to create larger objects (instead of larger objects being broken down into smaller elements)
what is appararent movement (gestalt)?
the principle behind the illusion of movement (wertheimer)
what are the 4 conditions of creating apparent movement?
- one light flashes on and off
- theres a period of darkness (lasting fraction of a second)
- second light flashing at a different position
- resulting in the perception that a light is moving from left to right, the period of darkness between the flashes is perceived as movement
what did Werheimer conclude from this apaprent movement experiment (gestalt)? (2)
- apparent movement cannot be explained by sensations because there is nothing in dark space between the flashing lights (nothing to perceive yet we perceive it as movement)
- the whole is different than the sum of its parts… the movement as a whole is different than 2 flashes of light
What are the 4 principles of gestalt psychology?
- principle of good ocntinuation: when connected, result in straight or smoothly curving lines are seen as belonging together and the lines tend to be seen in such way as to follow smoothest path. Objects that are overlapped by other objects are perceived as contiunuing behind that overlapping object
- principle of good figure OR principle of simplicity: every stimulus pattern is seen in such a way that the resulting structure is as simple as possible
- principle of similarity: similar things appear to be grouped together
“Every stimulus pattern is seen in such a way that the resulting structure is as simple as possible”
principle of simplicity/ or good figure
What are regularities in the environment?
characteristics of the environment that occur frequently. Regularities in the environment provide infromation we can use to resolve uncertainty…
what are two types of regularities?
- physical
2. semantic
what are physical regularities?
regularly occuring physical properties of the environment
what is the light from above assumption?
we usually assume that light is coming from above because in our natural envioronment, light is coming from the sun and aritifical light also comes from above
what are semantic regularities?
the characteristics associated with the functions carried out in different types of scenes
what is scene schema?
knoweldge of what a given scene typically contains
What is the bayesian inference?
our estimate of the probability of an outcome is determined by two factors:
1) the prior probability (our initial belief about the probability)
2) the extent to which the available evidence is consistent with the outcome (called likelihood)
Compare the four approaches to perception
helmholtz, regularities of environment and bayes all have in common the idea that we use data about the environment, gathered through our past experiences in perceiving to determine what is out there… so they support Top-down processing
gestalt psychology, emphasizes the idea that the principles of organization are built in
- they acknowledge that perception is affected by experience, but argued that built-in principles can override experience and therefore support bottom-up processing
What two tasks did Ungerleider and Mishkin present to the monkeys?
- object discrimination problem
2. landmark discrimination problem
What was the object discrimination problem that undergleider and mishkin presented to the monkeys?
monkey had to pick out the target object from novel object and push it aside to get food reward
What was the land discrimination problem that undergleider and mishkin presented to the monkeys?
the monkey received food if it removed the food well cover CLOSEST to the target
What is the perception pathway?
pathway from visual cortex to temporal lobe (ventral stream)
what is the action pathway?
pathway from the visual cortex to the parietal lobe (dorsal stream)
